Abstract
Hb La Coruña [β38(C4)Thr → Ile] is a new hemoglobin (Hb) variant that has an increased oxygen affinity. Clinically, this Hb leads to erythrocytosis. Hb La Coruña is an electrophoretically silent variant that can be detected by reversed phase high performance liquid chromatography (HPLC) and characterized by DNA sequencing. The patient was a 22-year-old Spanish male whose family lived in La Coruña, in the northwest of Spain. His mother was also a carrier.